How do cats purr? New finding challenges long-held assumptions | Science | AAAS
3 Ways to Treat Hoarseness in Cats - wikiHow Pet
The complicated truth about a cat's purr
Silencing of dogs & cats – Medically | Animal Blawg
I have two cats from the same litter. One is very vocal and both are very social and mild-mannered, but the other never makes vocal sound and hasn't since he was a